The present application represents U.S. national stage of international application PCT/SE98/023246 with an international filing date of Dec. 16, 1998. The international application claims priority to Swedish applications 9704710-4 and 9704713-8. Both of the Swedish applications were filed on Dec. 17, 1997.
The present invention relates to a medical device for effecting heat treatment and local delivery of a fluid medicament on body tissue presenting a predetermined section of a boundary wall of a passageway in a human or animal body comprising a catheter-like member for insertion into the passageway to a predetermined insertion position, the catheter-like member being provided with an inflatable balloon structure having a boundary wall which is inflatable against the body tissue when the catheter-like member is in the predetermined insertion position and delivery means for local delivery of the fluid medicament on the body tissue when the catheter-like member is in the predetermined insertion position, and a heating arrangement which is adapted to heat the body tissue when the catheter-like member is in the predetermined insertion position (hereinafter in part referred to as a xe2x80x9cmedical device of the type definedxe2x80x9d).
U.S. Pat. No. 5,380,319 [Olympus Optical Co., Ltd.] makes known a medical device of the type defined which is adapted for treatment of cancerous tissues in a body passageway (hereinafter xe2x80x9cthe Olympus devicexe2x80x9d). The balloon structure of the Olympus device is inflated by supplying a liquid thereto and the heating arrangement comprises a heating element in the balloon structure. With regard to the delivery means, this comprises a supply path for the medicament which terminates at one or more discharge arrangements mounted on the outer surface of the boundary wall of the balloon structure. When the catheter-like member of the Olympus device is in the predetermined insertion position, the balloon structure is inflated by the supply of liquid thereto and the medicament delivered on the cancerous tissue from the one or more discharge arrangements. The heat treatment of the cancerous tissue is then effected by activating the heating element so that the liquid in the balloon structure is heated and acts as a medium for heat transfer to the body tissue through the boundary wall of the balloon structure.
The present invention proposes to provide a medical device of the type defined with means for combining the delivery of the medicament with inflation of the balloon structure.
According to the present invention there is provided a medical device of the type defined in which the delivery means comprises a supply channel for supply of the fluid medicament to the balloon structure and a construction for the boundary wall of the balloon structure which is permeable to the fluid medicament whereby supply of the fluid medicament to the balloon structure along the supply channel when the catheter-like member is in the predetermined insertion position causes the balloon structure to inflate and fluid medicament to be delivered locally on the body tissue through the boundary wall of the balloon structure. The boundary wall of the balloon structure may be constructed so as to be fluid permeable by being porous permeable or perforate. Ordinarily, the medicament would be in liquid form in which case the boundary wall of the balloon structure would be constructed so as to be liquid permeable.
In an embodiment of the invention such as the one hereinafter to be described the heating arrangement comprises a heating element which is adapted to heat the fluid medicament prior to its discharge from the catheter-like member whereby the body tissue is able to be heated by fluid medicament delivered locally thereon through the boundary wall of the balloon structure when the catheter-like member is in the predetermined insertion position. This could be achieved by placing the heating element in the balloon structure. Alternately, the heating element may be placed in the supply channel of the catheter-like member or in a source of the medicament for connection to the supply path of the catheter-like member. A greater heating efficiency of the body tissue would result from the direct delivery of heated medicament thereon as compared to the indirect heating of the body tissue achieved by the Olympus device. Moreover, heating of the medicament may improve its efficacy.
In an embodiment of the invention such as the one hereinafter to be described the device further comprises a source of a fluid anaesthetic for supply to the supply channel for local delivery on the body tissue through the boundary wall of the balloon structure when the catheter-like member is in the predetermined insertion position. Other types of medicament could, of course, be administered by the medical device of the invention, further non-limiting examples being antibiotics, anti-cancer agents and anti-inflammatory agents.
In an embodiment of the invention such as the one hereinafter to be described the medical device is for effecting heat treatment and local delivery of the fluid medicament on the prostate gland of a human male body with the catheter-like member being adapted for insertion into the urethra of the human male body to the predetermined insertion position in which the boundary wall of the balloon structure is inflatable against the prostate gland.